Because if you boil it down to the bare basics those the country is in hock to; those that run the investment funds that own the country’s debt, as well as most of it’s essential services (power, water/sanitation, transport, etc.) have the entire country held hostage.

They simply threaten to melt the country down if the status quo isn’t protected.

Every single person’s pension/savings/entire life’s worth is dependant on these people not fucking everyone over. The actual country’s debt is in the same hands.

Shy of complete a meltdown and reset they have complete control over how the country is run, which is why things are the way the are.